@for $i from 12 through 60 {
    .fs#{$i} {
        font-size: #{$i}px;
    }
    .lh#{$i} {
        line-height: #{$i}px;
    }
}
@for $i from 0 through 15 {
    .letter-space-#{$i} {
        letter-spacing: #{$i}px;
    }
}

.fwb {
    font-weight: bold;
}

.fwn {
    font-weight: normal;
}